Lee Schuyler, Zhang Conggang, Liu Xuedong
From the Department of Chemistry and Biochemistry, University of Colorado-Boulder, Boulder, Colorado 80303.
From the Department of Chemistry and Biochemistry, University of Colorado-Boulder, Boulder, Colorado 80303
J Biol Chem. 2015 Jan 9;290(2):904-17. doi: 10.1074/jbc.M114.606798. Epub 2014 Nov 17.
Mutations in several genes, including PINK1 and Parkin, are known to cause autosomal recessive cases of Parkinson disease in humans. These genes operate in the same pathway and play a crucial role in mitochondrial dynamics and maintenance. PINK1 is required to recruit Parkin to mitochondria and initiate mitophagy upon mitochondrial depolarization. In this study, we show that PINK1-dependent Parkin mitochondrial recruitment in response to global mitochondrial damage by carbonyl cyanide m-chlorophenylhydrazine (CCCP) requires active glucose metabolism. Parkin accumulation on mitochondria and subsequent Parkin-dependent mitophagy is abrogated in glucose-free medium or in the presence of 2-deoxy-D-glucose upon CCCP treatment. The defects in Parkin recruitment correlate with intracellular ATP levels and can be attributed to suppression of PINK1 up-regulation in response to mitochondria depolarization. Low levels of ATP appear to prevent PINK1 translation instead of affecting PINK1 mRNA expression or reducing its stability. Consistent with a requirement of ATP for elevated PINK1 levels and Parkin mitochondrial recruitment, local or individual mitochondrial damage via photoirradiation does not affect Parkin recruitment to damaged mitochondria as long as a pool of functional mitochondria is present in the photoirradiated cells even in glucose-free or 2-deoxy-D-glucose-treated conditions. Thus, our data identify ATP as a key regulator for Parkin mitochondrial translocation and sustaining elevated PINK1 levels during mitophagy. PINK1 functions as an AND gate and a metabolic sensor coupling biogenetics of cells and stress signals to mitochondria dynamics.
包括PINK1和Parkin在内的多个基因发生突变,已知会导致人类常染色体隐性帕金森病。这些基因在同一途径中发挥作用,对线粒体动力学和维持起着关键作用。PINK1是将Parkin募集到线粒体并在线粒体去极化时启动线粒体自噬所必需的。在本研究中,我们表明,对羰基氰化物间氯苯腙(CCCP)引起的整体线粒体损伤,PINK1依赖的Parkin线粒体募集需要活跃的葡萄糖代谢。在无葡萄糖培养基中或CCCP处理后存在2-脱氧-D-葡萄糖的情况下,Parkin在线粒体上的积累以及随后Parkin依赖的线粒体自噬被消除。Parkin募集的缺陷与细胞内ATP水平相关,可归因于对线粒体去极化反应中PINK1上调的抑制。低水平的ATP似乎会阻止PINK1的翻译,而不是影响PINK1 mRNA的表达或降低其稳定性。与ATP对升高PINK1水平和Parkin线粒体募集的需求一致,只要在光照射细胞中存在一组功能性线粒体,即使在无葡萄糖或2-脱氧-D-葡萄糖处理的条件下,通过光照射引起的局部或单个线粒体损伤也不会影响Parkin募集到受损线粒体。因此,我们的数据确定ATP是Parkin线粒体易位和在自噬过程中维持PINK1水平升高的关键调节因子。PINK1作为一个“与”门和一个代谢传感器,将细胞的生物遗传学和应激信号与线粒体动力学联系起来。